1. Field of the Invention
This invention relates to a method for starting and regulating electromechanical valve adjusting devices for displacement-type machines and more particularly for starting and regulating valve actuating devices particularly suitable for operating valves or valve slides in internal combustion engines. The valve actuating devices are controlled by a control unit to set the dwell time of valves maintained in operating positions by any corresponding desired excitation time of an electromagnet triggered by the control unit.
2. Description of the Prior Art
A problem associated with starting internal combustion engines is that in order to initially start electromechanical valve adjusting devices such as disclosed in our copending Application entitled "Method of Controlling Reciprocating Four-Stroke Internal Combustion Engines", filed Feb. 3, 1984, under U.S. patent application Ser. No. 576,896 one must resort to special techniques to execute relatively large valve strokes with a high operating frequency. In Unexamined West German Patent Specification DE-OS No. 23 35 150, this problem is addressed with two dipping armature magnets, which results in a heavy form of construction and in relatively inefficient operating frequencies per mass unit of the armatures, so that only relatively low operating frequencies can be attained. Another possibile solution relies upon the use of very high currents for the starting process. However, this calls for very high starting voltages far above the standard operating starting voltages. The use of a very high voltage both for starting or initiating the valve control or adjusting process and for the subsequent operation of the valves during normal engine operational modes requires a limitation of the operating current with a series resistance. This results in a considerable power reduction during normal engine operation. According to U.S. Pat. No. 4,455,543, starting is accomplished with an additional biasing system.